Green anthraquinone dye and process of making same.



Patented July 21, 1903.

UNITED STATES PATENT OFFICE.

OTTO HESS, OF HOOHST-ON-THE-MAIN, GERMANY, ASSIGN OR TO FARB- Y WERKE, VORM. MEISTER, LUOIUS & BRUNING, OF HOOHST-ON-THE- MAIN, GERMANY, A CORPORATION OF GERMANY.

GREEN ANTHRAQUINONE DYE AND PROCESS OF MAKING SAME.

SPECIFICATION formingpart Of Letters Patent No. 73 4,325, dated July 21, 1903. Application filed April 18,1903. Serial No. 153,206. (No specimens.)

To all whom it may concern:

Be it known that I, OTTO HESS, Ph. D., a citizen of the Empire of Germany, residing at Hochst-on-the-Main, Germany, have invented certain new and useful Improvements in the Manufacture of a Green Ant-hraquinone Dyestuff, of which the following is a specification.

My invention consists in the manufacture of new dyestuff-sulfonic acids of the anthraquinone series which may be obtained by the action of sulfonating agents on dialphylamidodioxyanthraquinones. The latter are obtained by heating leuco-tetraoxyanthraqninones with primary aromatic amins-such as anilin, para toluidin, xylidin, and alphanaphthylamin and the 1ike in presence of salts of these amins. Leuco-tetraoxyanthraquinone is obtained by energetic acid reduction of para-dinitrodioxyanthraquinones.

When dry, the new dyestufi-sulfonic acids are green powders, soluble in water with a green color, which on addition of caustic alkalies turns to blue-green. The dyestulfs dye uninordanted wool green, the dyeings on chrome-mordanted wool being of a still more yellowish tint.

The manufacture of dialphylamidodioxy anthraquinones is illustrated as follows: One part by weight of leuco-tetraoxyanthraquinone and the same quantity of para-toluidin,

hydrochlorid are introduced into seven parts of molten para-toluidin, and the melt is heated for several hours to 90 to 110 centigradeuntil no unchanged leuco-tetraoxyanthraquinone is left. The mass is treated with two parts of pyridin, cooled, and filtered. The new body remains on the filter as dark crystals. They are soluble with great difficulty in indifierent solvents with-a green color. With caustic alkalies they yield crystallized salts, being also insoluble in hot anilin, pyridin, or chloroform.

To transform the condensationproduct into the dyestufi-sulfonic acid, one part, by weight, of it is dissolved in ten parts of sulfuric acid of 66 Baum, and the solution is heated to to 70 centigrade until a'test portion completely dissolves in water. The cold mixture of sulfonation is then poured into seventy parts of a solution of common salt, whereupon the dyestufi separates in green flakes.

They

are filtered, washed with a solution of common salt, and dried. The sodium salt of the.

new dyestuff-sulfonic acid thus obtained is a green powder soluble in water with a green and in diluted caustic-soda lye with a blue color. in water. The new dyestufi dyes nnmordanted wool green and wool mordanted with chromium compounds yellow-green. The dialphylamidodioxyanthraquinones obtained from anilin, xylidin, and naphthylamin or other primaryaromatic amins are transformed in a similar manner into dyestuff-sulfonic acids.

Having now described my invention, what I claim is l. The herein described process for the manufacture of new anthraquinone dyestufis which consists in treating dialphylamidodioxyanthraquinones with sulfonating agents and in isolating the sulfonic acids from the mixture of reaction in the manner herein described, substantially as set forth.

2. The. herein-described process for the manufacture of a new anthraquinone dyestufi which consists in treating di-para-toluidodh oxyanthraquinone with sulfonating agents and in separating the dyestufi obtained soluble in water in the manner herein described, substantially as set forth.

3. The herein-described new anthraquinone dyestuffs, being when dry green powders-soluble in water with a green, in concentrated caustic-soda lye with a blue-green color, dyeing unmordanted wool in green and wool mordanted with chromium compounds in yellow-green shades.

4. The herein described new anthraqui- The calcium salt is nearlyinsoluble none dyestufi obtained by sulfonating the di- In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

OTTO HESS.

Witnesses: I

ALFRED BRISBOIS, BERNHARD LYDECKER. 

